Article distribution system



3 Sheets-Sheet 1 Filed 001;. l, 1958 SECONDARY TRAY STATIONS PRIMARYDISTRIBUTOR STATIONS DISTRIBUTOR STATIONS SPACING STATION I/VVE/V TOR J:I I 1 mm mm m I April 1963 w. R. CLORE 3,087,598

. ARTICLE DISTRIBUTION SYSTEM Filed Oqt. 1, 1958 s Sheets-Sheet :5

a 6 90b I GAT GATE DETECTOR SOLEN SOLENOID 76 CIRCUIT f 5 .64 I780 I380B60 l78b 82b PLY RELAY RELAY '86 0 OLD I72 RII-ILAY I80 I460 I440 I46bDETECTOR CIRCUIT INVENTOR ELZZ/Q/AQW United States Patent 3,087,598ARTICLE DISTRIBUTION SYSTEM William R. Clore, Columbus, Ohio, assignorto Industrial Nucleonics Corporation, a corporation of Ohio Filed Oct.1, 1958, Ser. No. 764,579 3 Claims. (Ci. 1983$) This invention relatesto branched conveyor systems and routing means for articles carriedthereby; and more particularly it relates to an automatic gate controlsystem for distributing a fiow of articles to a plurality ofdestinations in accordance with indicia borne by said articles.

Although the invention is adapted for modification into various formsand is applicable to a variety of alternate uses, the same is hereinillustrated and described more specifically in connection with a postalservice installation wherein the system of the invention has utility inexpediting the sorting and delivery of mails.

At present, even in the largest postal installations the distribution ofsorted and semi-sorted mails is carried out almost entirely by manualmeans. Since the actual sorting process is a human hand and eyeoperation, the efficiency of the whole system depends on the degree ofutilization which is made to the available labor. In general, however,it is quite impossible to make correct and timely predictions as to theload distribution of incoming mails to be routed to various sortingareas. As a result, it frequently happens that some areas are swampedwith a deluge of inpom'ing mails and confusion reigns, whereas in otherareas personnel are relatively unoccupied.

It is the practice to conduct the hand sorting operation on the basis ofregional destinations such asgeographical areas, states, cities, zonesor carrier routes. Accordingly distribution cases are provided havingperhaps 50-400 regional separations. Previously it has generally beenthe'practice to have the contents of .a particular separation box pickedup only at appointed times. Often because of scheduling difiiculties asabove set forth, the quantity of mail addressed to a particulardestination exceeds the capacity of the compartments provided so thatsorters must resort to makeshift and unsatisfactory temporary storageexpedients which interfere with the routine sorting procedures, thusfurther slowing up the operation at a .critical time when sorting shouldbe proceeding at top efficiency.

These and other difiiculties are largely overcome by the i system of theinvention, whereby trays of mail with coded signal cards attached may beintermixed at random on a conveyor With-the assurance that each will beautomati cally and efficiently routed to its proper destination. It isan object of the invention to provide a branched conveyor system havingautomatic gate control means for distributing a flow of articles to aplurality of destinations in accordance with indicia borne by saidarticles.

It is another object to provide an "improved coding sys 'tem for articleidentifying indicia compatible with im proved reliable sensing meanstherefor.

It is also an object to provide a novel combination of indicia adaptedfor automatic identification by non-contacting sensing means of theproximity detector type.

Further, more specific and general objects of the invention will becomeapparent in the following detailed description, taken in connection withthe appended drawings, in which:

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veyor of FIG. 2, showing certain elements thereof in elevation.

FIG. 4 is a fragmentary side View of a portion of FIG. 3, taken on theline 44 thereof.

FIG. 5 is a fragmentary section on the line 5-5 of FIG. 4.

FIG. 6 is a section on the line 6-6 of FIG. 5.

FIG. 7 is a block diagram of the electrical circuitry of the inventionin accordance with one preferred embodiment thereof.

Referring to FIG. 1, there is shown schematically a portion of a postalinstallation including primary and secondary mail distribution areas. Inthe primary distribution area to the left a group of distributorsstations are indicated generally by the numerals 1048. Each distributorsstation as at it includes a plurality of distribution cases as at 2% and22, each manned by a distributor who sorts mail and distributes the sameinto a plurality of compartments provided in his distribution case,according to regional destinations. Each group of distributors issupplied with mail on a side ledge conveyor as at 24. In the figure, tensuch conveyors are shown entering from the left, it being understoodthat the conveyors as at 24 and 26 are loaded with incoming mail at aculling and postage cancelling area not shown.

As the individual separations in the distribution cases become full, orat appointed times, the distributors are notified by public addresssystem to place the contents of a certain separation box onto a conveyorbelt as at 30 which runs beneath the distribution cases. The belt 30carries this prirnary sort of loose mail to a tray station as at 4%,where the same is placed in trays adapted to carry signal cards whichare inserted into suitable holders on the trays. These trays, containingmail referred to as the primary sort, are placed on a conveyor 5!).

The conveyor 50, which also receives mail trays in a similar manner fromthe other distributors stations 12- 1h, carries the trays to a stop gateand spacing station 54 which holds and releases the trays one at a timeat spaced intervals onto a main feed conveyor 56 which transports thetrays to the secondary distribution area shown at the right side ofFIG. 1. Conveyor 56 is adapted for automatic diverting onto a pluralityof side ledge conveyors 53-68 servicing secondary distribution stationsas at 70 which are similar to the primary distributors stations as atIt) hereinabove described.

Each of the diverting gates as at 72 is controlled by an automatic cardreader as at 74- which reads the signal cards previously inserted intothe trays at the tray station as at tilt Each of the card readers isresponsive to only one particular combination of indicia. If thiscombination is detected by the reader on a card carried by a passingtray, the reader as at 74 will operate its associ ated diverting gate asat 72, routing the tray from the feed conveyor 56 to the associated sideledge conveyor as at 58.

This system is shown in more detail by FIG. 2, which illustrates themechanical features of one gate section in accordance with one preferredembodiment of the invention. A first tray 89, carrying letter mafl 32and a signal card 84 visually indicating the geographical destinationthereof, is shown passing on the feed conveyor 56. It is seen that thesignal card 84 is inserted into a side rack 86 provided on the tray 84 Asecond similar'tray 88, also on feed conveyor 56, is shown approachingthe junction of conveyor 56 with the side ledge conveyor 58 which runsat right angles thereto. The tray 88 also carries a signal card 90 whichis shown passing in front of the card reader 74 as is furtherillustrated in FIG. 3.

As the tray passes the card reader, it is seen that a relativelyflexible and curved metal deflector guide 92, fixed- 1y mounted on thefar (right) side of conveyor 56, urges the tray 88 toward the near(left) side of the conveyor and the card reader 74, so that the nearside of the passing tray is pressed into light frictional engagementwith a straight and relatively rigid guide rail 94. The guide rail 94 isfixedly mounted on the near side of the conveyor 56 and extends parallelthereto, in order to guide the tray 88 so that the signal card 90 willpass close to the reader 74 without contacting the same.

In connection with the card reader 74 is a cabinet 96 which containselectronic circuitry associated with the reader 74 and a relay systemadapted to automatically control the operation of the gate 72, to whichthe control cabinet is connected by an electrical cable 98.

Although any suitable type of power operated deflection gate may beused, the type illustrated comprises a rubber belt 100 carried on adriven pulley 102 and an idler pulley 104. The pulleys 102 and 104 arerotatably supported on journals comprising the end pieces of arectangular framework of which the top side member 106 is visible. Thisframework is pivotally supported at one end on an upstanding post 108fixedly secured to the floor, the side of the conveyor 56 or othersupport means. Hence each element of the framework 106 carrying the beltand pulleys is permitted to swing freely in a horizontal direction,being pivoted about the central axis of the driven pulley 102. Thepulley 102 is secured to an associated sprocket 110. An endless drivechain 112 passes around both the sprocket 110 and a coplanar sprocket114 carried on a drive shaft extending upwardly from a gear box 116. Thegear box 116 may be supplied with mechanical power through a shaft 118connected to the drive system (not shown) for the conveyor 56. It isseen therefore that the belt 100 revolves continuously around the axesof pulleys 102 and 104 whenever the conveyor 56 is in motion.

In order to actuate the gate 72 and thereby divert a passing tray ontothe side ledge conveyor 58, the frame 106 of the gate is provided with abell crank 120 whose free end 122 is pivotally secured to the piston rod124 of a fluid operated piston and cylinder driving device. The endframe 126 of the drive cylinder 128 is pivotally mounted on anupstanding anchor post 130 which may be rigidly secured either to thefloor or the side of the conveyor 56. Fluid is conducted to and from theendports of cylinder 128 through a pair of flexible pressure hoses 132and 134 which connect respectively to a pair of solenoid actuated valves136 and 138. Valves 136 and 138 are further connected to a source offluid pressure such as the air pressure supply line 140. It will beunderstood that if an air cylinder is used to actuate the gate, eachvalve is provided with an exhaust port vented to the atmosphere, whereasif a hydraulic cylinder is used a suitable return pipe to the oilreservoir will be provided.

Normally fluid pressure from line 140 may be applied to line 134 throughvalve 138, so that the piston rod 124 will be extended, thus maintainingthe gate in the position illustrated, at the side of, and parallel to,the conveyor 56. When a gate energizing signal is received from thecabinet 96 via cable 98, valve 138 disconnects line 134 from thepressure supply line 140 and vents line 134 to the atmosphere or to afluid return pipe. Simultaneously valve 136 connects line 132 to thefluid pressure supply line 140 so that the piston rod 124 will beretracted, causing the gate to swing across the path of the tray 88 inthe direction of the arcuate arrow 141. As the tray 88 advancing onconveyor 56 strikes the gate, the traveling surface of the belt 100frictionally engages the leading end of the tray and turns it toward theside ledge conveyor 58.

In most cases it is appropriate that the drive mechanism for the sideledge conveyor 58 be normally idle, and that the same should advanceonly when a tray is delivered thereon. Accordingly a pair of limitswitches 142 and 144 are provided to start and stop the conveyor 58.Hence when the gate 72 diverts a tray, the same will strike limit switch142, causing the conventional drive system (not shown) for conveyor 58to be placed in operation. Thereupon the tray is carried off on conveyor58 to the point where it strikes the second limit switch 144, therebystopping the conveyor 58.

The switch 144 which stops the movement of conveyor 58 may also beutilized to actuate the release mechanism for gate 72, which has beenheld in operated position by holding circuits in cabinet 96. To this endthese circuits are connected to switch 144 through a cable 146.

Referring now to FIGS. 4, 5 and 6, it is seen that the card reader 74includes an insulation block 160 having a plurality of spaced holes asat 162 bored therein, each adapted to receive a non-contacting metaldetector probe as at 164. The block 160 may extend through a rectangularopening in the cabinet 96 and be secured thereto by means of bolts as at166.

The block 160 is of such a length that when the base flange as at 164aof a probe as at 164 is seated at the rear of one of the bored openingsin the block, the active end of the probe sits flush with the end of theblock which points in the direction of a passing signal card 90.

As is shown in the sections of FIG. 5 and FIG. 6, each signal cardpreferably comprises three bonded laminations a, 90b and 90c of plasticor other electrically insulating material. The center lamination 90b ispunched, drilled or molded with a plurality of holes as at 168 eachadapted to accommodate a metal disc as at 170. It is apparent that whena card assembly passes in front of the reader 74, the presentation of ametal disc in direct alignment with one of the metal detector probeswill trigger the metal detector.

It is seen that the pattern of holes as at 168 in the center lamination90b of the card corresponds to the pat tern of the holes as at 162 inthe block which accommodates the metal detector probes. In theillustrated arrangement, only two probes 164 and 172 are used in onecard reader. correspondingly, only two metal discs and 174 are mountedin each signal card.

The probe 164 is connected by a flexible conductor 176 to an electronicpanel 178, and similarly probe 172 is connected by a flexible conductor180 to a duplicate electronic panel 182. Thus a probe may be easilyinserted in, or removed from, the rear of any hole in the insulatingblock 160 for the purpose of setting up or altering the code to whichthe card reader 74 will respond.

Suitable circuitry for the gate control system is shown in FIG. 7,wherein it is seen that the probe 164 is con nected by conductor 176 toa metal detector circuit 178a adapted to trigger an associated relay17812. Similiarly the probe 172 is connected by conductor 180 to adetector circuit 182a adapted to trigger a relay 18217. The relays anddetector circuits are connected to a suitable power supply 184. Whenboth metal detector relays 17% and 1821) are energized simultaneously, aconventional hold relay 186 is also energized from the power supply.Once the hold relay is energized, it will remain energized even thoughone or both of the metal detector relays 1781; and 182b is de-energized,due to its holding circuit from the power supply which includes contacts144a of the limit switch 144 and conductors 146a and 146b. When the holdrelay is energized, it connects the power supply 184 to the gatesolenoids 136a and 138:: which actuate the fluid pressure control valves136 and 138 shown in FIG. 2. These valves in turn control the drivecylinder 128 which aotuates the gate 72.

The operation of .the system may be summarized as follows, referring toFIGS. 2 and 7. The card reader 74 is adapted to respond only to a signalcard having metal discs in both of the particular two holes shown inFIG. 6, which holes correspond to the location of the probes 164 and 172in the insulating block 160. Cards having discs in other locations inthe same horizontal rows may trigger the metal detectors independently.

However, the hold relay 186 cannot be energized by operation of eitherrelay 17812 or 1821) alone, or by operation of both relays at differenttimes. Hence the gate 72 will not interfere with through traffic onconveyor 56 of trays bearing signal cards adapted to trigger gates onother side ledge conveyors receiving mail to other destinations.

However, when a passing signal card has its metal discs located inposition to activate both metal detectors simultaneously, both relays178k and 18% will close their contacts at the same time, completing acircuit from the power supply 184 which energized the hold relay 186.The hold relay will then complete its holding circuit through limitswitch contacts 144a and simultaneously apply power to gate solenoids136a and 138a. Solenoid 136a will operate valve 136 so as to connect theair pressure line 140 through air hose 132 to the rod end of aircylinder 128, forcing the piston (not shown) to the rear of the cylinderand causing the piston rod 124 to retract. Simultaneously solenoid 138awill operate valve 138 so as to disconnect the air pressure line 140from air hose 134 and to vent the hose 134 to the atmosphere, thusrelieving the pressure in the closed end of cylinder 128.

The retracting operation of the drive cylinder will actuate the gate 72as hereinabove described, diverting the tray 88 onto the conveyor 58.Operation of limit switch 142' by the tray starts the conveyor 58, whichcarries the tray onward until it contacts the limit switch 144. Switch144 stops conveyor 58, and simultaneously opens its contacts 144a. Sincethe relays 178i) and 18211 were deenergized after the discs 170 and 174passed the metal detector probes, the opening of switch contacts 144adeenergizes hold relay 186 which in turn de-energizes solenoids 136a and138a. Accordingly the gate 72, which has meanwhile been held across thepath of conveyor 56, is restored to its original position.

Although the invention is not limited to any particular spatialarrangement of the metal detector probes and the metallic elements to bedetected thereby, it will be noted that the signal card and the blockshown in FIGS. 4 and 6 are adapted to a spatial code wherein a singlemaster column of holes is spaced some distance from a group of holescomprising a plurality of columns. One probe is always located in onehole of the master column as is illustrated by the position of probe164, and similarly one metal disc always occupies one hole of the mastercolumn, as is illustrated by the position of disc 170. The master columnis spaced from the secondary group of columns by a distance greater thanthe maximum width of the secondary group. Thus no combination of discsin the secondary columns alone can trigger both the master probe and asecondary probe simultaneously, as is required to operate the gate. Thatis to say, the signal card is read only when the master column of thesignal card is in proximity to the master probe, which is a uniqueposition of the signal card in its travel past the card reader.

The invention likewise is not limited to any particular number of metaldetectors. Although only two are used in the illustrated card reader,three or more may be provided. Hence the particular embodiment of theinvention shown and described is meant to be illustrative only and notrestrictive, since it is obvious that many changes and modifications canbe made within the spirit and scope of the invention as is set forth inthe appended claims.

What is claimed is:

1. An article distribution system comprising a main conveyor bearing aseries of articles to be distributed, a plurality of branch conveyorsspaced along the path of said main conveyor and intersecting the same, adiverter gate at each such intersection, said gate being movable from afirst position clearing the path of said articles on said main conveyorto a second position for diverting an article on said main conveyor tothe intersecting branch conveyor, a non-metallic signal card carried byeach of said articles, means for detachably securing said card to itsassociated article, a plurality of metallic elements spatially arrangedon each of said signal cards in accordance with a destination-indicativecoded pattern, a plurality of metal detectors each responsive to thepresence of an electrical conduct-or without physical contact therewithand adapted to be triggered by proximity thereto,

means for mounting said metal detectors adjacent said intersection andspatially arranged relative thereto in accordance with alocation-indicative coded pattern, guide means mounted on one side ofsaid main conveyor and adjacent said intersection for directing the flowof said articles in spaced relation to said metal detectors, wherebysaid metallic elements are guided in proximity to said metal detectorswithout contacting the same, and means energized by synergetic action ofsaid metal detectors on coincidence of said location-indicative patternwith said destination-indicative pattern on a passing article foractuating said gate to said second position.

2. A system as in claim 1 wherein each of said metal detectors comprisesa probe unit and an electronic chassis unit, wherein said metal detectormounting means comprises a non-metallic block having a plurality ofreceptacles each adapted to receive said probe unit, and which includesflexible conductors connecting said chassis unit to said probe unit topermit selection and alteration of said location-indicative pattern bytransferring said probe from one receptacle to another.

3. A system as in claim 1 wherein each of said signal cards comprises alamination of non-metallic sheets, one of said sheets having a pluralityof spaced apertures therein, at least two of said apertures eachcontaining one of said metallic element-s electrically insulated fromother elements on said card.

References Cited in the file of this patent UNITED STATES PATENTS1,797,864 Harlandt Mar. 24, 1931 1,909,481 Allen May 16, 1933 2,063,230Crady Dec. 8, 1936 2,773,658 Von Otteren et al Dec. 11, 1956 2,794,535Hauschild et al. June 4, 1957 OTHER REFERENCES Meeh. Handling, articleby Mumby, January 1958, pages 19-26.

1. AN ARTICLE DISTRIBUTION SYSTEM COMPRISING A MAIN CONVEYOR BEARING ASERIES OF ARTICLES TO BE DISTRIBUTED, A PLURALITY OF BRANCH CONVEYORSSPACED ALONG THE PATH OF SAID MAIN CONVEYOR AND INTERSECTING THE SAME, ADIVERTER GATE AT EACH SUCH INTERSECTION, SAID GATE BEING MOVABLE FROM AFIRST POSITION CLEARING THE PATH OF SAID ARTICLES ON SAID MAIN CONVEYORTO A SECOND POSITION FOR DIVERTING AN ARTICLE ON SAID MAIN CONVEYOR TOTHE INTERSECTING BRANCH CONVEYOR, A NON-METALLIC SIGNAL CARD CARRIED BYEACH OF SAID ARTICLES, MEANS FOR DETACHABLY SECURING SAID CARD TO ITSASSOCIATED ARTICLE, A PLURALITY OF METALLIC ELEMENTS SPATIALLY ARRANGEDON EACH OF SAID SIGNAL CARDS IN ACCORDANCE WITH A DESTINATION-INDICATIVECODED PATTERN, A PLURALITY OF METAL DETECTORS EACH RESPONSIVE TO THEPRESENCE OF AN ELECTRICAL CONDUCTOR WITHOUT PHYSICAL CONTACT THEREWITHAND ADAPTED TO BE TRIGGERED BY PROXIMITY THERETO, MEANS FOR MOUNTINGSAID METAL DETECTORS ADJACENT SAID INTERSECTION AND SPATIALLY ARRANGEDRELATIVE THERETO IN ACCORDANCE WITH A LOCATION-INDICATIVE CODED PATTERN,GUIDE MEANS MOUNTED ON ONE SIDE OF SAID MAIN CONVEYOR AND ADJACENT SAIDINTERSECTION FOR DIRECTING THE FLOW OF SAID ARTICLES IN SPACED RELATIONTO SAID METAL DETECTORS, WHEREBY SAID METALLIC ELEMENTS ARE GUIDED INPROXIMITY TO SAID METAL DETECTORS WITHOUT CONTACTING THE SAME, AND MEANSENERGIZED BY SYNERGETIC ACTION OF SAID METAL DETECTORS ON COINCIDENCE OFSAID LOCATION-INDICATIVE PATTERN WITH SAID DESTINATION-INDICATIVEPATTERN ON A PASSING ARTICLE FOR ACTUATING SAID GATE TO SAID SECONDPOSITION.